JPH0788527A - Catenary controller - Google Patents

Abstract

PURPOSE:To easily determine the optimum correction value of a height set value in height control. CONSTITUTION:The optimum tension set value T* is calculated by referring to a correction curve when the advance position of a welding point into a catenary zone is inputted to an optimum tension set value calculating section 17. A catenary height Href' at a fixed point is calculated in accordance with the optimum tension set value T* by using the catenary equation meeting the position of the welding point. The set value Href of the catenary height set by a height setter 8 is subtracted from the catenary height Href' in a subtractor 18. The set value Href is added to this difference in an adder 19 and further, the actually measured value of a catenary sensor 5 is subtracted therefrom in a subtractor 9 and the resulted difference is sent to a height controller 11, by which the speed of a driven bridle roll 4 is controlled. As a result, the catenary is held at the set value Href of the set height at the fixed point of the catenary C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catenary control device in a steel process line or the like.

[0002]

2. Description of the Related Art Conventionally, for catenary control in a steel process line, etc., a bridle roll is provided on each of the entrance side and the exit side of the catenary loop. I keep it. Specific controls include a tension control method in which a tension detector is installed in the catenary zone to keep the tension constant, and a height control method in which a catenary sensor is installed to keep the height constant.

In these controls, when the thickness of the material such as the steel plate forming the catenary changes and the cross-sectional area fluctuates, the catenary passes as the welding point where the preceding and following materials are connected passes through the catenary zone. Shape changes. FIG. 4 schematically shows the change. The catenary shape shown by the solid line in the figure shows the case where the cross-sectional area of the material forming the catenary is constant, and the broken line shows the case where the cross-sectional area of the preceding material is larger than that of the following material. The chain line shows the case where the cross-sectional area of the preceding material is smaller than that of the following material.

Since the shape of the catenary fluctuates as the welding point passes, the material will contact the structural obstacle at the fluctuated portion. Therefore, it is necessary to control the catenary shape by controlling the tension in the case of tension control and controlling the height in the case of height control. For example, in the case of tension control, the tension set value is corrected by simulation to keep the distance between the catenary and the structural obstacle constant, the variation Δh in all the catenary zones is minimized, or the lowest point ( The position of bottom dead center) can be kept constant. Specifically, using the correction curve shown in FIG. 5, assuming that the tension set value of the preceding material is T ₁ , the tension set value of the following material is T ₂ , and the position of the welding point is x, the optimum tension set value T ^* Is calculated by the following equation.

[0005]

[Equation 1] T ^* = T ₁ + d (x) · (T ₂ −T ₁ )

According to this equation, the optimum tension set value T ^* is T ₁ at the start point and the optimum tension set value T ^* at the end point ^.
Becomes T ₂ .

[0007]

However, when the catenary shape is to be controlled by controlling the height, the correction curve is as shown in FIG. 6, and the correction curve changes depending on the ratio of the sectional areas. Moreover, this change is not simply proportional to the cross-sectional area ratio. Therefore, conventionally, there has been a problem that it is necessary to create a large number of correction curves and it is difficult to obtain an optimum correction value. The present invention has been made to solve the above problems, and an object thereof is to provide a catenary control device that can easily obtain an optimum correction value of a height set value in height control. is there.

[0008]

In order to achieve the above object, the present invention provides a catenary sensor for detecting a catenary height at a fixed point of a catenary zone, and an optimum value of the catenary height at the fixed point of the catenary zone. Height setting device, means for detecting the welding point position when a welding point connecting different materials having different characteristics when forming a catenary enters the catenary zone, and welding prepared in advance Referring to the tension correction curve showing the relationship between the point position and the optimum tension setting value for it,
The means for calculating the optimum tension set value at the detected welding point position and the catenary curve formula for each of the preceding material forming the front catenary and the trailing material forming the rear catenary of the welding point in the catenary zone are set to the welding point position. , The optimum tension set value and known unit length / weight of preceding material, unit length / weight of trailing material, and catenary span, and the catenary height at the fixed point using the corresponding catenary curve formula according to the position of the welding point with respect to the fixed point. The height correction amount and the catenary height detected by the catenary sensor are calculated by subtracting the set optimum catenary height value from the calculated height. And means for calculating the correction amount of tension in the front bridal roll.

[0009]

In the present invention, the catenary height at the fixed point of the catenary zone is detected by the catenary sensor, and the optimum value of the catenary height at the fixed point is set by the height setter. When a welding point formed by connecting different materials having different characteristics when forming a catenary enters the catenary zone, the position of the welding point is detected. Then, the optimum tension set value at the detected welding point position is calculated with reference to the tension correction curve that shows the relationship between the welding point position and the optimum tension set value prepared for it.

At the same time, the catenary curve formulas for each of the preceding material forming the front catenary and the trailing material forming the rear catenary of the welding point in the catenary zone are determined by the detected welding point position, the calculated optimum tension set value and It is calculated from the known long-term unit weight of the preceding material, the long-term unit weight of the following material, and the catenary span. Next, the catenary height at the fixed point is calculated by using the corresponding catenary curve formula according to the position of the welding point with respect to the fixed point.

Further, the optimum value of the set catenary height is subtracted from the calculated height of the catenary to calculate the height correction amount. From the obtained height correction amount and the catenary height detected by the catenary sensor, The correction amount of the tension of the bridal roll located in the front is calculated. This makes it possible to control the catenary height by finding the optimum height of the fixed-point catenary with only one simulation.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention.
In the figure, a catenary C to be controlled includes a guide roller 2 arranged immediately after the main bridle roll 1 and a guide roller 3 arranged immediately before the sub bridle roll 4.
Formed between and. The space between the guide rollers 2 and 3 becomes a catenary zone, and the height of the catenary C at a specific position (hereinafter referred to as a fixed point) in the catenary zone is detected by the catenary sensor 5.

Catenary C is bridle roll 1,4
Controlled by. That is, when the speed command value Nmref is input to the speed control unit 6, the speed control unit 6 controls the rotation of the motor 7 based on the speed command value Nmref, so that the bridle roll 1 is driven at a predetermined tension and speed. It On the other hand, with respect to the bridle roll 4, in the normal case where the same material is continuously fed to form the catenary C, the catenary sensor 5 changes from the set value Href of the catenary height set by the height setter 8. The actual measurement value Hist of the detected catenary height is subtracted by the subtractor 9, and the obtained difference is sent to the height control adjuster 11.

The height control adjuster 11 converts the input difference into a speed command value Nhref and sends it to the speed control unit 12. The speed control unit 12 controls the rotation of the motor 13 based on the input speed command value Nhref. Thereby, the tension and speed of the bridle roll 4 are controlled, and the optimal catenary C is formed. A drooping characteristic is added by connecting a droop resistor 14 in parallel to the speed control unit 12.

When different materials pass through, the advancing position of the welding point where the ends of the different materials are connected to the catenary zone is detected by the detection means (not shown) and the optimum tension is set in the height correction circuit 15. It is input to the value calculator 16. A tension correction curve similar to that shown in FIG. 5 is stored in advance in the calculation unit 16, and by referring to this correction curve, the optimum tension set value T ^* is calculated and the height correction calculation unit is calculated. Sent to 17. Height correction calculator 1
In 7, the catenary height Href ′ at the fixed point where the catenary sensor 5 is installed is calculated based on the optimum tension set value T ^* after any one of the catenary formulas described below is selected according to the position of the welding point. It

Next, the subtracter 18 subtracts the set value Href of the catenary height set by the height setter 8 from the catenary height Href ', and the obtained difference ΔH.
The ref is sent to the adder 19. The adder 19 sends the difference Δ
The set value Href is further added to Href, and the obtained sum is sent to the subtractor 9. After that, the speed of the bridle roll 4 is controlled as described above, and the catenary height at the fixed point of the catenary C is held at the set value Href.

Next, the formula representing the catenary curve used in the height correction calculator 17 will be described with reference to the explanatory view of FIG. In FIG. 2, the guide rollers 2,
The curve formula of the catenary C formed during 3 is as follows when the traveling materials are the same.

[0018]

[Equation 2]

S _A and D _A in the equation are respectively expressed by the following equations.

[0020]

[Equation 3]

[0021]

[Equation 4]

Here, T in the equations 2 to 4 is a tension set value (k
g), W is the material weight (kg / m), S is the catenary span (m), x is the height from the starting point of the catenary (m), y
Is the horizontal distance (m) from the starting point of the catenary, and H is the vertical distance (m) between the guide rollers 2 and 3. Further, when the welding point enters the catenary zone, the catenary equation of the trailing material is as shown in Equation 5, and the catenary equation of the preceding material is as in Equation 6. In the formula, x _z is the position of the welding point (horizontal distance m), W ₁ is the weight of the preceding material (kg / m), and W ₂ is the weight of the following material (kg / m).

[0023]

[Equation 5]

[0024]

[Equation 6]

Here, S _B , D _B , S _A and D _A in the equations 5 and 6
Are respectively expressed by the following equations.

[0026]

[Formula 7] S _B = a ₁ · (S−x _z ) ² + x _z + a ₂ · x _z ² + a ₃ · T

[0027]

[Equation 8] D _B = a ₄ · S _B ² · 1 / T

[0028]

[Formula 9] S _A = x _z + a ₅ · (x _z −S _B )

[0029]

[Formula 10] D _A = -a ₄ · x _z ² · T / 2 · a ₄ · S _B ·
_{x z · 1 / T + a} 6 · (x z -S B) 2 · 1 / T

Here, a _{1 to} a ₆ in the equations 7 to 10 are all constants, and are as follows.

[0031]

[Number 11] _{a 1 = W 2/2 ·} W 2 · S

[0032]

[Equation 12] a ₂ = -1 / 2 · S

[0033]

[Formula 13] a ₃ = -H / W ₂ · S

[0034]

[Number 14] a ₄ = -W _2/2

[0035]

[Expression 15] a ₅ = -W ₂ / W ₁

[0036]

[Number 16] ^{_{a 6 = -W 2 2/2}} · W 1

Next, the calculation of the height correction calculator 17 when the welding point enters the catenary zone will be described with reference to the flowchart of FIG. First, in the calculation unit 17, S _B ,
D _B , S _A and D _A are calculated (S1). Next, the position x _{z of the} welding point and the horizontal position x _s of the catenary sensor 5 are compared, and if the welding point is located in front of the catenary sensor 5 (S2 Yes), it is represented by Formula 6. The optimum height at the sensor position x _s is obtained using the catenary formula for the preceding material (S3).

When the welding point exceeds the catenary sensor 5 (S2 No), the optimum height at the sensor position x _s is calculated using the catenary formula for the trailing material expressed by the mathematical formula 5 (S4).

According to this embodiment, it is possible to easily realize what was not possible to optimize the correction at the time of passing the welding point by the conventional height control, by calculating using the correction of the tension control. You can Further, even in the case of obtaining a value close to the optimum value, it is conventionally necessary to perform a plurality of simulations depending on the ratio of the cross-sectional areas of the preceding material and the following material, but in the embodiment, it can be realized by one simulation. it can.

[0040]

As described above, according to the present invention, the optimum tension set value is obtained for each position of the welding point by referring to the tension correction curve, and then the catenary height at the fixed point is calculated and obtained. The calculated value of the tension is calculated by comparing the measured value with the value measured by the sensor. As a result, it is possible to easily realize what was not possible to optimize the correction at the time of passing through the welding point by the conventional height control by one simulation using the correction of the tension control.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an exemplary embodiment of the present invention.

FIG. 2 is an explanatory diagram of a catenary curve formula used in Examples.

FIG. 3 is a flowchart showing a processing operation of a height correction calculation unit in FIG.

FIG. 4 is an explanatory diagram schematically showing a change in catenary accompanying passage of a welding point.

FIG. 5 is a graph showing a tension correction curve used for conventional tension control.

FIG. 6 is a graph showing a height correction curve used for conventional height control.

[Explanation of symbols]

 1 main bridle roll 2 guide roller 3 guide roller 4 secondary bridle roll 5 catenary sensor 6 speed control unit 7 motor 8 height setter 9 subtractor 11 height control adjuster 12 speed control unit 13 motor 14 droop resistance 15 height correction Circuit 16 Optimum tension set value calculator 17 Height correction calculator 18 Subtractor 19 Adder C Catenary

Claims (1)

[Claims] 1. A catenary sensor for detecting a catenary height at a fixed point of the catenary zone, a height setter for setting an optimum value of the catenary height at the fixed point of the catenary zone by an external input, and a catenary for forming a catenary. A means for detecting the welding point position when a welding point connecting dissimilar materials with different characteristics enters the catenary zone, and a tension correction indicating the relationship between the welding point position prepared in advance and the optimum tension set value for it. A means to calculate the optimum tension set value at the detected welding point position by referring to the curve, and a catenary curve for each of the preceding material forming the front catenary and the trailing material forming the rear catenary of the welding point in the catenary zone Weld position, optimum tension set value and known unit length of leading material, unit weight of trailing material, catenary A means for calculating from the pan, a means for calculating the catenary height at the fixed point using the corresponding catenary curve formula according to the position of the welding point with respect to the fixed point, and an optimum value for the catenary height set from the calculated catenary height And a means for calculating the correction amount of the tension in the front side bridal roll from the height correction amount and the catenary height detected by the catenary sensor. A characteristic catenary control device.